Automatic Critical Angle Refractometers
with Temperature Control

• Peltier controlled sample holder +10°C to + 70 °C
• Full range 1.3320 - 1.7000 index
• Accurate and repeatable measurements independent of the operator
• Fully Automatic - simply load a small sample and press one button.
• Digital readout of refractive index, Brix and sample temperature.
• Temperature compensated Brix readings for samples from 15 - 40 °C
• Only a small volume (0.3ml) sample needed
• Load up to 2 more additional scales
• RS232 data port and parallel Centronics port.
• Built in diagnostics

Digital automatic high performance refractometer
The ATRW2 is a new refractometer from Schmidt + Haensch featuring a Peltier temperature controlled sample holder. Like its predecessor the unit is a microprocessor controlled, critical angle refractometer for measuring the optical density of a wide range of liquid media from low to high viscosity, and independent of opacity and color.
This is new instrument is a very comprehensive laboratory refractometer on account of its temperature control capabilities, large index range, and high accuracy and resolution. 

Refractometry and Concentration
Refractometers are widely used to measure the amount of dissolved substances in solutions containing mainly sucrose. The relationship between refractive index and the amount of dry substance content is well known for sucrose and is the basis of the Brix scale which is measure of the number of grams of sucrose present per 100 grams of aqueous sugar solution. (50 Brix means 50 grams of solid per 100 gm of solution) This relationship holds for a large number of similar substances and so the Brix scale is widely used in the food industry. Unfortunately the refractive index of a sugar solution changes with temperature while its solid content remains the same. ( The same refractive index at different temperatures correspond to different Brix values.)
The ATRW2 can be programmed with other concentration scales in addition to Brix.